Film processor with floating cover

ABSTRACT

A film-processing apparatus having an arcuate row of processing tanks with open upper ends for admitting a film carrier vertically into and out of the treating liquids in the tanks, the film carrier being advanced step-by-step relative to the tanks and moved into and out of each tank by a conventional feeding mechanism. A protective cover of stable and buoyant plastic is floated on the developer liquid in one tank to prevent aeration of the portion of the liquid under the cover, and has two shaped openings surrounding the upper ends of two immersion zones within the liquid for admitting the carrier with a close clearance fit into the liquid.

United States Patent [1113,M12,124

[72] Inventor Wilbur G. Allen 2,710,832 6/1955 Harr .1 204/48 1807 Kelly SL, Oceanside, Calif. 92054 3,062,123 1 1/1962 Limbergerm... 95/89 [21] P 8095 Primary Examiner-Samuel S. Matthews [22] filed 1969 Assistant Examiner-Robert P. Greiner [451 Patented Aug-31,1971 Attorney-Fulwider, Patton, Rieber, Lee & Utecht [54] 1F lLM PROCESSOR WITH FLOATING COVER 10 Claims, 5 Drawing Figs. [52] 11.8.4131 95/89 D, ABSTRACT: A film pmcessing apparatus having an arcuate 95/14 row of processing tanks with open upper ends for admitting a [51] Int. Cl 603d 3/00, film Cartier vertically into and out ofthe treating liquids in the 603d 3/10 tanks, the film carrier being advanced step-by-step relative to [50] Field of Search 95/89,90, the tanks and moved into and out of each tank by a com/em 9196* 14 tional feeding mechanism. A protective cover of stable and buoyant plastic is floated on the developer liquid in one tank [56] Reerenm cued to prevent aeration of the portion of the liquid under the UNITED STATES PATENTS cover, and has two shaped openings surrounding the upper 1,572 12/1952 Luboshez 95/94X ends of two immersion zones within the liquid for admitting 2,623,650 12/1952 Allen 95/14 X the carrier with a close clearance fit into the liquid.

FILM PROCESSOR WITH FLOATING COVER BACKGROUND OF THE INVENTION The invention relates to the processing of photographic film strips through successive treating tanks to develop exposed images on the strips, and has particular reference to an automatic film-processing apparatus wherein each piece of film is held on a carrier for moving the strip, automatically and step by step, into alignment with immersion zones of successive treating tanks and vertically into and out of each tank, thereby immersing the film in appropriate fluids to complete the development ofthe film.

One type of automatic processing apparatus for accomplishing the foregoing is disclosed in US. Pat. No. 2,576,204, wherein it will be seen that several tanks are arranged along an arcuate path and filled to selected initial levels with the appropriate fluids, including at least one developer and the other necessary baths for the processing of the film. Each film strip is moved along the arcuate path, above the tanks, and is dipped vertically at least one time into each tank by the mechanism supporting and moving the film carrier.

This general type of processing apparatus has found wide acceptance in the coin-operated self-photography field, being combined with an automatic camera mechanism and installed in public places such as bus and train stations, department stores and the like. For a selected price, a customer is able to make one or more photographs of himself and, after a short delay for processing, receives the completed strip of photographs automatically from the machine. Another embodiment, with much of the associated apparatus, is shown in US. Pat. No. 2,9l6,976.

Such machines are serviced periodically for replenishment and renewal of the processing baths with water and chemicals, the life of the chemicals being the primary consideration in the frequency of servicing required and also having an important bearing on the quality of the photographs. Most seriously affected by the passage of time is the chemical solution used as the developer, which is subject to deterioration primarily as a result of aerial oxidation.

For example, it has been found that the highly active developers presently in use perform satisfactorily for as many as 600 film strips, over a maximum period of about 3 weeks, before deteriorating to an extent requiring replacement. Replenishment to maintain the liquid level may be required at more frequent intervals but is a relatively simple operation. After the permissible number of film strips or the maximum time period, whatever occurs first, complete servicing is required. Accordingly, it will be evident that anything which prolongs the useful life of processing chemicals has important advantages, both from the standpoint of reducing the cost of chemicals and from the standpoint of reducing the frequency, and therefore the cost, of servicing.

SUMMARY OF THE INVENTION The present invention significantly increases the useful life of the developer in a film-processing apparatus of the foregoing general character, in an extremely simple and inexpensive manner, and thus significantly reduces the cost of operating and maintaining such an apparatus. In fact, it has been found that the permissible number of strips and the maximum period of time, in apparatus of the type disclosed in the aforesaid patents, can be approximately doubled with the present invention.

More specifically, the invention resides in the combination with a developer tank in a film-processing apparatus having at least one carrier of preselected cross-sectional shape for moving film strips step by step, from one tank to another, and moving the carrier vertically into and out of the immersion zones of successive tanks, of a protective cover for the developer tank composed of buoyant material and having the shape of the inside of the tank so as to fit closely within the tank and float on the developer, the cover being formed with at least one opening shaped and positioned to admit the carrier into the immersion zone with a relatively close, clearance fit. This substantially reduces the exposed area of the developer and correspondingly reduces the aeration and evaporation of the developer, for an increased useful life on the order of twice that achieved with conventional tanks.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. i is a fragmentary perspective view of part of an apparatus for processing film strips and embodying the novel features of the present invention, the apparatus including a developer tank shown in full lines between two additional processing tanks, a cover for the developer, and a film carrier in the process of being immersed in the liquid in the developer tank;

FIG. 2 is a plan view of the cover and the developer tank;

FIG. 3 is a fragmentary cross-sectional view taken in vertical plane through the developer tank, the cover and the film carrier while the latter is in the lowered position;

FIG. 4 is a perspective view of the protective cover; and

FIG. '5 is a view similar to FIG. 2 showing an alternative form of the invention.

DETAILED DESCRIPTION As shown in the drawings for purposes of illustration, the invention is incorporated in an automatic film-processing apparatus having an arcuate row of treating tanks (three of which are shown in FIG. l and indicated by the reference numbers 10, l1 and 12) formed with open upper ends and containing bodies of treating liquids through which a film strip 13 is to be processed to develop one or more exposed images on the strip. In a conventional manner, the film strip is held in a carrier 14 which is supported on a feeding or indexing mechanism (not shown) for advancing the carrier step by step along the row of tanks and moving, the carrier substantially vertically, thereby to immerse the strip in each tank for a selected interval of treating and then. to lift the strip out of the tank preparatory to movement on to the next tank for the next step in the treating process.

As described in detail in the aforesaid patents, the tanks typically are arranged side by side in the arcuate row and may form a full circle or annulus, each tank preferably having a horizontal cross section that has the shape of a truncated sector of a circle. The feeding mechanism is centrally mounted within the circle of tanks, and supports a series of carriers that are indexed one by one, from tank to tank, when the apparatus is in operation. As shown herein, the illustrative carrier 14 comprises an arm that is secured at its inner end to the feeding mechanism with a horizontal inner end portion projecting radially outwardly to overlie the row of tanks, a downwardly extending central portion 17 and an outwardly and downwardly inclined portion 18 terminating in a tab 19 that is suitably secured to the inner side of a film holder 20 that completes the carrier 14.

The holder 20 is a hollow, vertically elongated tube having a restricted lower end and an open, :funnellike upper end 21 through which the film strip 13 is inserted into the holder. Preferably, the holder has flat and generally parallel inner and outer sides, at least one side preferably being partially open to permit the treating fluids to flow around the emulsion side of film strip therein. Herein, these flat sides are generally in vertical planes perpendicular to the radii of the row of tanks in FIGS. ll-3, and the inner side of the holder has angled vanes of the usual type for circulating the treating fluids over the inner emulsion side of the strip as the carrier is raised and lowered.

As previously stated, different liquids are provided in the tanks to accomplish the successive processing steps required for the film strip. The tank ill, with which the present inven tion is primarily concerned, contains a developer llla composed of different chemical constituents selected for the par ticular film being processed, and the next tank 112 in the row may contain a water rinse. Other tanks (not shown) in the row typically contain appropriate washes and other agents used in film processing. Each tank is sufficiently deeper than the length of the strip 13, for complete immersion of the strip, and the walls of the tanks are vertical. In practice, the cross-sectional area of the tank has been made substantially greater than that of the carrier.

In accordance with the present invention, a protective cover 22 is disposed within the developer tank 11 in contact with the developer therein, and is shaped to fit closely within the upper end portion of the tank to minimize exposure of the developer to air. This cover is formed with at least one opening 23 of limited area surrounding the immersion zone at the surface of the developer, and is shaped to pass the end portion of the carrier 14, including the holder 20, through the cover with a clearance fit, thus avoiding any possibility of interference as a result of permissible variations in the path of the carrier. With this arrangement, the exposed area of the developer is reduced to a practical minimum to minimize aerial oxidation and evaporation without interfering with the operation of the processor. In the first illustrative embodiment (which is patterned after the commercial form presently in the widest use),

I the reduction in exposed area is on the order of 60 percent,

and the useful life of the developer is substantially doubled. I

With reference to FIGS. 1-4, it will be seen that the cover 22 is substantially flat sheet of material having the shape of a truncated sector of a circle, with rounded corners corresponding to the rounding of the corners of the developer tank 11, and with outside dimensions providing a loose, sliding fit of the cover within the tank while avoiding any unnecessary clearance space between the edges of the cover and the walls of the tank. The material is chemically and physically stable in the developer, and also is buoyant therein so as to rise and fall with changes in the level in the tank and thus to remain in contact with the surface ofthe liquid.

A preferred material for the cover 22 is polyethylene having a density on the order of 0.90-0.97, the density of typical developers being approximately 1,0. Polyethylene is stable in developers, is relatively inexpensive, does not warp, and may be formed in sheets that are virtually free of burrs so as to avoid interfering with the runoff of any liquid that may be splashed or dripped onto the upper surface of the cover. The surface tension is such that the liquid runs freely off the cover and back into the tank. Other plastics, of course, have similar physical and chemical properties and may be used instead of polyethylene.

I-Ierein, the cover 22 shown in FIGS. 14 is formed with two identical, generally T-shaped openings 23 spaced along the arcuate path of the carrier 14 and each having a transversely elongated outer portion 23a shaped to pass the holder 20 through the cover with a clearance fit, and an inwardly narrowing portion 23b for accommodating the adjacent outer portions 17, 18 and 19 of the carrier arm, as shown most clearly in FIGS. 2 and 3. The primary consideration in the sizing and shaping of the openings 23, of course, is the shape of the carrier structure that must pass vertically through the cover, together with lateral variations that can occur in the path of passage. The opening should be made large enough to avoid interference with the vertical motion, but no larger than is reasonably necessary to avoid such interference.

With two openings 23 in the cover 22 spaced along the path, the carrier 14 may be inserted twice in the developer tank 11 in laterally spaced, or indexed positions, for twice the developing time provided by one immersion. This practice is well known in the art, and is accomplished simply by making the developer tank twice as wide, angularly, as the representative the tanks and to the carrier's arcuatc path. Again, the shape of the cover corresponds to the cross-sectional shape of the developer tank 11, and the clearance around the holder during vertical movement thereof through the cover is only sufficient to avoid interference.

It will be seen in FIG. 3 that the cover 22 sinks within the developer 11a to a level determined by the relative densities of the developer and the plastic of the cover, but the top surface of the cover remains above the level of the developer as a result of the buoyancy of the plastic.'Accordin gly, only the necessary surface areas of the developer surrounded by the openings, that is, the upper ends of the immersion zones, are exposed to air, thus minimizing both aerial oxidation and evaporation. As evaporation occurs, at the reduced rate controlled by the cover, the latter is free to fall with the liquid level and to remain in contact with the surface of the liquid, therebymaintaining its effectiveness in reducingaeration and evaporation.

From the foregoing, it will be evident that the present invention provides a novel, relatively simple, and very effective and inexpensive approach to the problem of increasing the useful life of the developer in a film-processing apparatus, and

added quickly and easily to existing machines, of which large numbers are presently in commercial use, for an immediate and inexpensive improvement in operating characteristics. The shape of the cover, of course, can be modified for different shapes of tanks, and the shape of the openings can be modified for different shapes of carriers.

Accordingly, it will be apparent that, while specific forms of the invention have been illustrated and described, various modifications can be made without departing from the spirit and scope of the invention.

I claim as my invention: 1

1. In combination with an apparatus for developing film strips and having a series of tanks with open upper ends, at least one of said tanks being a developer tank of preselected cross-sectional'shape and area for holding a body of developing liquid subject to deterioration by exposure to atmosphere, and a film carrier movable laterally into alignment with successive tanks and vertically into and out of each tank to immerse a film strip on the carrier into the tank before moving to the next tank, said carrier having a preselected cross-sectional shape in a horizontal plane and occupying a cross-sectional area in said developer tank constituting materially less than said preselected area, the improvement comprising: a sheet of buoyant material having the shape of the cross section of said developer tank and fitted therein in closely spaced relation with said tank so as to form a cover floating on said liquid, and means defining at least one opening in said cover surrounding said cross-sectional area in said developer tank in closely spaced relation therewith, for movement of said carrier vertically into and out of said liquid through said opening, thereby to reduce the area of exposure of said liquid to atmosphere to that required for insertion and removal of the carrier including sufficient clearance to avoid interference with said movement.

2. The improvement defined in claim I in which said tanks are arranged on an arc, each having a cross-sectional shape constituting part ofa sector ofa circle, and in which said cover constitutes a similar part of a sector of a circle.

3. The improvement defined in claim 2 in which said developer tank is angularly wide enough to receive said carrier' in two successive, spaced positions thereof, for two immersions in said liquid, said cover having two side-by-side openings spaced apart along said arc and shaped to admit said carrier through the cover in closely spaced relation therewith.

4. The improvement defined in claim 1 in which said cover is composed of stable plastic material that is impervious to said liquid and has a density less than the liquid.

5. The improvement defined in claim 1 in which said carrier:

includes a vertically elongated film holder with a cross-sectional shape that is elongated in "the direction of movement of the carrier from tank to tank, and a supporting arm connected to said holder on one elongated side thereof, said opening having one side portion that is elongated in the direction of movement of said carrier from tank to tank, thereby to admit said holder through said covering, and also having a portion shaped to admit said supporting arm through said covering.

6. The improvement defined in claim 1 in which said carrier includes a film holder with a cross-sectional shape that is elongated transversely of the direction of movement of said carrier from tank to tank, and a supporting arm connected to said holder at one end thereof, said opening being elongated transversely of said direction of movement and sufficiently long to admit both said holder and said arm through said cover.

7. In combination with a developer tank having an open upper end of preselected cross-sectional shape defined by vertical walls; a body of developer liquid in said tank having an upper surface adjacent said upper end; a holder for a strip of film having a preselected cross-sectional shape adapted to be mounted in said tank; and means for first carrying said holder into alignment with an immersion zone having an upper end constituting part of said cross-sectional area, then moving the holder downwardly into said zone and then upwardly out of the zone to treat a strip of film, and then carrying the holder out of alignment with the tank, the improvement comprising: a cover sized and shaped to fit closely and movably within said upper end in contact with the upper surface of said liquid, said cover being composed of stable buoyant material so as to float on the liquid and prevent aeration of the portion under the cover and having an opening overlying said upper end of said immersion zone to admit said holder into and out of said liquid.

8. The combination defined in claim 7 in which said cover is a sheet of polyethylene having a flat. upper surface and the same shape as the cross-sectional shape of said tank.

9. The combination defined in claim 7 in which said tank has the cross-sectional shape of a truncated sector of a circle, and said cover is similarly shaped and sufiiciently smaller to move within the tank in closely spaced relation therewith.

10. The combination defined in claim 9 in which said cover is formed with two openings sized to admit said holder with a close clearance fit into said tank, and angularly spaced along said circle to define the upper ends of 'two immersion zones in said tank. 

1. In combination with an apparatus for developing film strips and having a series of tanks with open upper ends, at least one of said tanks being a developer tank of preselected crosssectional shape and area for holding a body of developing liquid subject to deterioration by exposure to atmosphere, and a film carrier movable laterally into alignment with successive tanks and vertically into and out of each tank to imMerse a film strip on the carrier into the tank before moving to the next tank, said carrier having a preselected cross-sectional shape in a horizontal plane and occupying a cross-sectional area in said developer tank constituting materially less than said preselected area, the improvement comprising: a sheet of buoyant material having the shape of the cross section of said developer tank and fitted therein in closely spaced relation with said tank so as to form a cover floating on said liquid, and means defining at least one opening in said cover surrounding said cross-sectional area in said developer tank in closely spaced relation therewith, for movement of said carrier vertically into and out of said liquid through said opening, thereby to reduce the area of exposure of said liquid to atmosphere to that required for insertion and removal of the carrier including sufficient clearance to avoid interference with said movement.
 2. The improvement defined in claim 1 in which said tanks are arranged on an arc, each having a cross-sectional shape constituting part of a sector of a circle, and in which said cover constitutes a similar part of a sector of a circle.
 3. The improvement defined in claim 2 in which said developer tank is angularly wide enough to receive said carrier in two successive, spaced positions thereof, for two immersions in said liquid, said cover having two side-by-side openings spaced apart along said arc and shaped to admit said carrier through the cover in closely spaced relation therewith.
 4. The improvement defined in claim 1 in which said cover is composed of stable plastic material that is impervious to said liquid and has a density less than the liquid.
 5. The improvement defined in claim 1 in which said carrier includes a vertically elongated film holder with a cross-sectional shape that is elongated in the direction of movement of the carrier from tank to tank, and a supporting arm connected to said holder on one elongated side thereof, said opening having one side portion that is elongated in the direction of movement of said carrier from tank to tank, thereby to admit said holder through said covering, and also having a portion shaped to admit said supporting arm through said covering.
 6. The improvement defined in claim 1 in which said carrier includes a film holder with a cross-sectional shape that is elongated transversely of the direction of movement of said carrier from tank to tank, and a supporting arm connected to said holder at one end thereof, said opening being elongated transversely of said direction of movement and sufficiently long to admit both said holder and said arm through said cover.
 7. In combination with a developer tank having an open upper end of preselected cross-sectional shape defined by vertical walls; a body of developer liquid in said tank having an upper surface adjacent said upper end; a holder for a strip of film having a preselected cross-sectional shape adapted to be mounted in said tank; and means for first carrying said holder into alignment with an immersion zone having an upper end constituting part of said cross-sectional area, then moving the holder downwardly into said zone and then upwardly out of the zone to treat a strip of film, and then carrying the holder out of alignment with the tank, the improvement comprising: a cover sized and shaped to fit closely and movably within said upper end in contact with the upper surface of said liquid, said cover being composed of stable buoyant material so as to float on the liquid and prevent aeration of the portion under the cover and having an opening overlying said upper end of said immersion zone to admit said holder into and out of said liquid.
 8. The combination defined in claim 7 in which said cover is a sheet of polyethylene having a flat upper surface and the same shape as the cross-sectional shape of said tank.
 9. The combination defined in claim 7 in which said tank has the cross-sectional shape of a truncated sector of a circle, and said cover is similarly shaped and sufficiently smaller to move within the tank in closely spaced relation therewith.
 10. The combination defined in claim 9 in which said cover is formed with two openings sized to admit said holder with a close clearance fit into said tank, and angularly spaced along said circle to define the upper ends of two immersion zones in said tank. 